The multi-store model of memory

Question 1

what is coding?

Answer 1

coding refers to the format or ‘type’ of information stored in each memory store

Question 2

coding for short-term memory

Answer 2

acoustic

Question 3

coding for long-term memory

Answer 3

semantic

Question 4

explain a study investigating coding

Answer 4

Aim: Baddeley (1966) investigated coding
Method: gave 4 10-word lists to 4 participant groups (acoustically similar, acoustically dissimilar, semantically similar, semantically dissimilar)
Findings: immediate recall was worst for acoustically similar
recall after 20 mins was worst with semantically dissimilar
Conclusion: suggests that coding in STM is acoustic - recalling acoustically similar was most difficult as the recalling similar sounds caused confusion in recall

Question 5

what is capacity?

Answer 5

capacity refers to the volume of information/data which can be kept in any memory store at any one time

Question 6

explain a study into capacity - CHUNKING

Answer 6

Miller (1956) suggested that the capacity for STM is 7 +/- 2 items and the capacity for LTM is unlimited - based on the idea that things come in groups of 7
He also suggested that our capacity for remembering information can be increased if we chunk items together - by finding links between things and group them together e.g. phone numbers are learnt this way

Question 7

explain a study into capacity - DIGIT SPAN

Answer 7

Aim: Jacobs (1887) studied STM capacity
Method: Used a digit span test to examine the capacity of STM for numbers and letters
Used a sample of 443 female students (ages 8-19)
Participants had to repeat back a string of digits or letters in the same order which gradually increased in numbers until the participants could no longer recall the sequence
Findings: students had an average span of 7.3 letters and 9.3 words
Conclusion: supports Miller’s 7+-2 theory

Question 8

what is duration?

Answer 8

duration refers to the amount of time that information can be stored in each memory store

Question 9

explain a study into duration - STM

Answer 9

Aim: Peterson and Peterson (1959) studies the duration of STM
Method: 24 undergrads recalled 3-letter trigrams at different intervals - to prevent maintenance rehearsal the students counted backwards in 3s from a specific number until they were asked to recall the letters (interference)
Findings: the longer the interval the less accurate the recall
at 3 secs - 80% recalled correctly
at 18 secs - 10% recalled correctly
Conclusion: STM has a limited duration of ~18secs and that if we are unable to rehearse information it will not be passed to LTM (MSM)

Question 10

evaluations of Peterson and Peterson’s study into the duration of STM

Answer 10

• sample of 24 psychology students - students may have studied the MSM and may have demonstrated demand characteristics by changing their behaviour to assist the experimenter
• sample of 24 psychology students - memories may be different to that of other people as they may have studied strategies for memory improvement - results cannot be generalised to non-psychology students
• low levels of ecological validity - unlikely that in everyday life you would need to memorise 3 letter trigrams - unable to apply results to everyday examples of memory - unable to conclude if the duration of STM is longer for more important information
  + highly controlled lab experiment - control over extraneous variables - easy to replicate

Question 11

explain a study into duration - LTM

Answer 11

Aim: Bahrick (1975) investigated duration of LTM using 392 American uni grads
Method: shown photos from yearbook and given a group of names for each photo and asked to select the name that matched the photos
Findings: after 14 years - 90% were able to match names and faces correctly
after 47 years - 60%
Conclusion: people could remember certain types of information for a long time - supports MSM and the idea that LTM has unlimited duration and is semantically encoded

Question 12

evaluations for Bahrick’s research into duration of LTM

Answer 12

• lacks population validity - used sample of american uni grads - cannot generalise results to other population - cannot conclude whether other populations would demonstrate the same ability to recall names and faces
• unable to explain whether LTM becomes less accurate overtime due to limited duration or whether LTM gets worse with age - unable to determine if LTM has an unlimited duration
  + high levels of ecological validity - real life memories and information was used - results reflect our memory for real-life events and can be applied to everyday memory

Question 13

who created the MSM?

Answer 13

Atkinson & Shiffrin (1968)

Question 14

what is the MSM?

Answer 14

information processing model of memory
information is shown to flow through in one direction (linear)
stores hold on to information before being passed on or lost (passive)

Question 15

what are the 3 MSM stores?

Answer 15

sensory register
STM
LTM

Question 16

what is the sensory register?

Answer 16

sensory information coming from the senses is detected and recorded

Question 17

features of sensory
register

Answer 17

coding: depends on sense organ e.g. vision = iconic, sound = echoic, touch = haptic, taste = gustatory, smell = olfactory
capacity: very large - must contain all the sense impressions for all senses in each moment
duration: very short (~250milliseconds) - so much information cannot be retained for very long

Question 17

how is information passed from sensory register to STM?

Answer 17

attention

Question 17

features of STM

Answer 17

coding: acoustically (sound/ spoken words)
capacity: 7+-2
duration: 18-30secs

Question 18

how is information passed between STM and LTM?

Answer 18

STM –> LTM - rehearsal
LTM –> STM - retrieval
information lost - displacement (new info) or decay (over time)

Question 19

types of rehearsal

Answer 19

maintenance rehearsal - repeating information
elaborative rehearsal - linking info already in LTM
rehearsal loop - extends duration of STM by verbal rehearsal

Question 20

features of LTM

Answer 20

coding: semantically (meaning)
capacity: unlimited - information can still be in the LTM but not accessible
duration: unlimited

Question 21

evidence that STM and LTM are separate processes

Answer 21

Glanzer and Cunitz (1966)
Method: asked participants to recall word lists
Findings: recall was much stronger for words at the start and end of the list
Conclusion: suggests STM and LTM are separate stores with words first heard entering LTM and being called (primacy effect) and the most recent words being held by STM and being recalled (recency effect) and the middle words were in the STM but were displaced by later words

Question 22

evaluations of the MSM

Answer 22

• lab experiments are highly artificial and lack external validity - low ecological validity so may not be generalisable to more naturalistic situations like school and work - lacks mundane realism - not real-life situations
  + artificial nature ensures less extraneous variables - measures clearly memory and limits of memory - only way of uncovering mental structure of memory
• inferences are made based on behaviour observed during experiments - so they may be incorrect
  + large capacity and short duration of SR matches evolutionary theory that as much information as possible is gathered from the environment but only important information is processed
• further research shows STM and LTM are not unitary stores but are multiple types - WMM
• MSM lacks face validity and is too simplistic - e.g. LTM’s of taste and smell, capacity of STM changes over time